Better Health Through Chemistry
Molecular sieves are basically desiccants like silica gel, only more efficient. They absorb moisture as well as solvents and pollutant gases. Chemically the molecular sieve is a crystalline form of sodium alumino-silicate (zeolite), a porous solid with small pores approximately 4 angstroms in size. They are like small chemical sponges which minimize the effects of vinegar syndrome.
The sieves absorb moisture, acetic acid, and methylene chloride, which are contaminants released during the natural aging of film. The sieves resemble silica gel packets shipped with cameras and electronic equipment. The polypropylene packets are placed within the archival film storage cans with the cleaned and preserved film.
|
